1. Technical Field
The present disclosure relates to apparatus for assembling a lens group.
2. Description of Related Art
Camera modules are included as a feature in a wide variety of devices, such as digital cameras and mobile phones. Generally, a camera module includes a lens module comprising a lens barrel and at least one lens group mounted in the lens barrel. Typically, a lens group includes various optical elements (e.g. lenses, spacers, and filters) received in the lens barrel.
A lens group is arranged and assembled in a lens barrel by use of an assembling apparatus (e.g. supporting table) as needed. A previous supporting tray (see FIG. 6) for assembling a lens group, includes a base plate 10, a plurality of holes 101 defined in the base plate 10. The base plate 10 has a carrying protrusion 1011 in the holes 101 extending outwardly from the base plate 10, and is configured for carrying the optical elements.
During assembly of a lens module, referring to FIG. 7, firstly, a first lens 201 is placed on the carrying protrusion 1011. Secondly, a number of spacers 202 and a number of second lenses 203 are assembled into the corresponding hole 101 one by one in a manner that optical axes of the first and second lenses 201, 203 lie in a same line. The first lens 201, the second lenses 203, and the spacers are bonded together with adhesive thereby forming a lens group 20. The lens group 20 is configured to be assembled into the lens barrel (not shown) to obtain a lens module.
To ensure proper alignment of the optical axes of the first and second lenses 201, 203, a diameter of each hole 101 must be equal to that of the respective optical elements assembled therein. That is, outer side surfaces of the optical elements are in airtight contact with an inner surface of the hole. Thus, when a lens is assembled into the hole, the air in the hole remains in the hole and is pressed by the lens, which may cause misalignment of the optical axes.
Therefore, what is desired is an apparatus for assembling a lens group that is capable of overcoming the aforementioned problems.